Founders reward: changed index computation, added new test and some refactoring.

src/chainparams.cpp

@@ -341,25 +341,31 @@ bool SelectParamsFromCommandLine()
 
 // Block height must be >0 and <=last founders reward block height
 // Index variable i ranges from 0 - (vFoundersRewardAddress.size()-1)
-std::string CChainParams::GetFoundersRewardAddress(int nHeight) const
+std::string CChainParams::GetFoundersRewardAddressAtHeight(int nHeight) const
 {
     int maxHeight = consensus.GetLastFoundersRewardBlockHeight();
     assert(nHeight>0 && nHeight<=maxHeight);
 
-    size_t i = (size_t)floor((double(nHeight-1)/maxHeight)*vFoundersRewardAddress.size());
+    size_t addressChangeInterval = (maxHeight + vFoundersRewardAddress.size()) / vFoundersRewardAddress.size();
+    size_t i = nHeight / addressChangeInterval;
     return vFoundersRewardAddress[i];
 }
 
 // Block height must be >0 and <=last founders reward block height
 // The founders reward address is expected to be a multisig (P2SH) address
-CScript CChainParams::GetFoundersRewardScript(int nHeight) const
+CScript CChainParams::GetFoundersRewardScriptAtHeight(int nHeight) const
 {
     assert(nHeight > 0 && nHeight <= consensus.GetLastFoundersRewardBlockHeight());
 
-    CBitcoinAddress address(GetFoundersRewardAddress(nHeight).c_str());
+    CBitcoinAddress address(GetFoundersRewardAddressAtHeight(nHeight).c_str());
     assert(address.IsValid());
     assert(address.IsScript());
     CScriptID scriptID = get<CScriptID>(address.Get()); // Get() returns a boost variant
     CScript script = CScript() << OP_HASH160 << ToByteVector(scriptID) << OP_EQUAL;
     return script;
 }
+
+std::string CChainParams::GetFoundersRewardAddressAtIndex(int i) const {
+    assert(i>=0 && i<vFoundersRewardAddress.size());
+    return vFoundersRewardAddress[i];
+}

src/chainparams.h

@@ -78,8 +78,9 @@ public:
     const std::vector<SeedSpec6>& FixedSeeds() const { return vFixedSeeds; }
     const Checkpoints::CCheckpointData& Checkpoints() const { return checkpointData; }
     /** Return the founder's reward address and script for a given block height */
-    std::string GetFoundersRewardAddress(int height) const;
+    std::string GetFoundersRewardAddressAtHeight(int height) const;
-    CScript GetFoundersRewardScript(int height) const;
+    CScript GetFoundersRewardScriptAtHeight(int height) const;
+    std::string GetFoundersRewardAddressAtIndex(int i) const;
 protected:
     CChainParams() {}
 

src/gtest/test_foundersreward.cpp

@@ -69,9 +69,17 @@ TEST(founders_reward_test, create_testnet_2of3multisig) {
 #endif
 
 
-#define NUM_TESTNET_FOUNDER_ADDRESSES 48
+// Utility method to check the number of unique addresses from height 1 to maxHeight
+void checkNumberOfUniqueAddresses(int maxHeight, int nUnique) {
+    std::set<std::string> addresses;
+    for (int i=1; i<=maxHeight; i++) {
+        addresses.insert(Params().GetFoundersRewardAddressAtHeight(i));
+    }
+    ASSERT_TRUE(addresses.size()==nUnique);
+}
 
-TEST(founders_reward_test, testnet) {
+
+TEST(founders_reward_test, general) {
     SelectParams(CBaseChainParams::TESTNET);
 
     CChainParams params = Params();
@@ -79,24 +87,16 @@ TEST(founders_reward_test, testnet) {
     // For Testnet, the first address is derived from the old script. 
     // FOUNDERS_REWARD_SCRIPT = a9146708e6670db0b950dac68031025cc5b63213a49187
     //                address = 2N2e2FRfP9D1dRN1oRWkH7pbFM69eGNAuQ4
-    EXPECT_EQ(params.GetFoundersRewardScript(1), ParseHex("a9146708e6670db0b950dac68031025cc5b63213a49187"));
+    EXPECT_EQ(params.GetFoundersRewardScriptAtHeight(1), ParseHex("a9146708e6670db0b950dac68031025cc5b63213a49187"));
-    EXPECT_EQ(params.GetFoundersRewardAddress(1), "2N2e2FRfP9D1dRN1oRWkH7pbFM69eGNAuQ4");
+    EXPECT_EQ(params.GetFoundersRewardAddressAtHeight(1), "2N2e2FRfP9D1dRN1oRWkH7pbFM69eGNAuQ4");
 
     int maxHeight = params.GetConsensus().GetLastFoundersRewardBlockHeight();
     
     // If the block height parameter is out of bounds, there is an assert.
-    EXPECT_DEATH(params.GetFoundersRewardScript(0), "nHeight");
+    EXPECT_DEATH(params.GetFoundersRewardScriptAtHeight(0), "nHeight");
-    EXPECT_DEATH(params.GetFoundersRewardScript(maxHeight+1), "nHeight");
+    EXPECT_DEATH(params.GetFoundersRewardScriptAtHeight(maxHeight+1), "nHeight");
-    EXPECT_DEATH(params.GetFoundersRewardAddress(0), "nHeight");
+    EXPECT_DEATH(params.GetFoundersRewardAddressAtHeight(0), "nHeight");
-    EXPECT_DEATH(params.GetFoundersRewardAddress(maxHeight+1), "nHeight"); 
+    EXPECT_DEATH(params.GetFoundersRewardAddressAtHeight(maxHeight+1), "nHeight"); 
-    
-    // Check that different addresses are used for testnet
-    std::set<std::string> addresses;
-    for (int i=1; i<=maxHeight; i++) {
-        addresses.insert(params.GetFoundersRewardAddress(i));
-    }
-    ASSERT_TRUE(addresses.size()==NUM_TESTNET_FOUNDER_ADDRESSES);
-
 }
 
 
@@ -107,11 +107,18 @@ TEST(founders_reward_test, mainnet) {
     CChainParams params = Params();
 
     int maxHeight = params.GetConsensus().GetLastFoundersRewardBlockHeight();
-    std::set<std::string> addresses;
+    checkNumberOfUniqueAddresses(maxHeight, NUM_MAINNET_FOUNDER_ADDRESSES);
-    for (int i=1; i<=maxHeight; i++) {
+}
-        addresses.insert(params.GetFoundersRewardAddress(i));
+
-    }
+
-    ASSERT_TRUE(addresses.size()==NUM_MAINNET_FOUNDER_ADDRESSES);
+#define NUM_TESTNET_FOUNDER_ADDRESSES 48
+
+TEST(founders_reward_test, testnet) {
+    SelectParams(CBaseChainParams::TESTNET);
+    CChainParams params = Params();
+
+    int maxHeight = params.GetConsensus().GetLastFoundersRewardBlockHeight();
+    checkNumberOfUniqueAddresses(maxHeight, NUM_TESTNET_FOUNDER_ADDRESSES);
 }
 
 
@@ -122,11 +129,7 @@ TEST(founders_reward_test, regtest) {
     CChainParams params = Params();
 
     int maxHeight = params.GetConsensus().GetLastFoundersRewardBlockHeight();
-    std::set<std::string> addresses;
+    checkNumberOfUniqueAddresses(maxHeight, NUM_REGTEST_FOUNDER_ADDRESSES);
-    for (int i=1; i<=maxHeight; i++) {
-        addresses.insert(params.GetFoundersRewardAddress(i));
-    }
-    ASSERT_TRUE(addresses.size()==NUM_REGTEST_FOUNDER_ADDRESSES);
 }
 
 
@@ -146,3 +149,24 @@ TEST(founders_reward_test, slow_start_subsidy) {
     
     ASSERT_TRUE(totalSubsidy == MAX_MONEY/10.0);
 }
+
+
+// Verify the number of rewards going to each mainnet/testnet address
+TEST(founders_reward_test, per_address_reward) {
+    SelectParams(CBaseChainParams::TESTNET);
+    CChainParams params = Params();
+
+    int maxHeight = params.GetConsensus().GetLastFoundersRewardBlockHeight();    
+    std::multiset<std::string> ms;
+    for (int nHeight=1; nHeight<=maxHeight; nHeight++) {
+        ms.insert(params.GetFoundersRewardAddressAtHeight(nHeight));
+    }
+
+    ASSERT_TRUE(ms.count(params.GetFoundersRewardAddressAtIndex(0)) == 17708);
+    for (int i = 1; i <= 46; i++) {
+        ASSERT_TRUE(ms.count(params.GetFoundersRewardAddressAtIndex(i)) == 17709);
+    }
+    ASSERT_TRUE(ms.count(params.GetFoundersRewardAddressAtIndex(47)) == 17677);
+
+}
+

src/main.cpp

@@ -3090,7 +3090,7 @@ bool ContextualCheckBlock(const CBlock& block, CValidationState& state, CBlockIn
         bool found = false;
 
         BOOST_FOREACH(const CTxOut& output, block.vtx[0].vout) {
-            if (output.scriptPubKey == Params().GetFoundersRewardScript(nHeight)) {
+            if (output.scriptPubKey == Params().GetFoundersRewardScriptAtHeight(nHeight)) {
                 if (output.nValue == (GetBlockSubsidy(nHeight, consensusParams) / 5)) {
                     found = true;
                     break;

src/miner.cpp

@@ -342,7 +342,7 @@ CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn)
             txNew.vout[0].nValue -= vFoundersReward;
 
             // And give it to the founders
-            txNew.vout.push_back(CTxOut(vFoundersReward, chainparams.GetFoundersRewardScript(nHeight)));
+            txNew.vout.push_back(CTxOut(vFoundersReward, chainparams.GetFoundersRewardScriptAtHeight(nHeight)));
         }
 
         // Add fees